The current ARMv7 PMU backend indexes event counters from two, with
index zero being reserved and index one being used to represent the
cycle counter.
This patch tidies up the code by indexing from one instead (with zero
for the cycle counter). This allows us to remove many of the accessor
macros along with the counter enumeration and makes the code much more
readable.
Acked-by: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch ensures that integers are used to represent event indices in
the ARMv7 PMU backend. This ensures consistency between functions and
also with the arm_pmu structure.
Acked-by: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The ARMv7 perf backend mixes up u32 and unsigned long, which is rather
ugly.
This patch makes the ARMv7 PMU code consistently use the u32 type
instead.
Acked-by: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch removes const qualifiers from instances of struct arm_pmu,
and functions initialising them, in preparation for generalising
arm_pmu usage to system (AKA uncore) PMUs.
This will allow for dynamically modifiable structures (locks,
struct pmu) to be added as members of struct arm_pmu.
Acked-by: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (237 commits)
ARM: 7004/1: fix traps.h compile warnings
ARM: 6998/2: kernel: use proper memory barriers for bitops
ARM: 6997/1: ep93xx: increase NR_BANKS to 16 for support of 128MB RAM
ARM: Fix build errors caused by adding generic macros
ARM: CPU hotplug: ensure we migrate all IRQs off a downed CPU
ARM: CPU hotplug: pass in proper affinity mask on IRQ migration
ARM: GIC: avoid routing interrupts to offline CPUs
ARM: CPU hotplug: fix abuse of irqdesc->node
ARM: 6981/2: mmci: adjust calculation of f_min
ARM: 7000/1: LPAE: Use long long printk format for displaying the pud
ARM: 6999/1: head, zImage: Always Enter the kernel in ARM state
ARM: btc: avoid invalidating the branch target cache on kernel TLB maintanence
ARM: ARM_DMA_ZONE_SIZE is no more
ARM: mach-shark: move ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-sa1100: move ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-realview: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-pxa: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-ixp4xx: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-h720x: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
ARM: mach-davinci: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size
...
The PMUv2 specification reserves a number of event encodings
for common events.
This patch adds these events to the common event enumeration
in preparation for PMUv2 cores, such as Cortex-A15.
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The comment about measuring TLB misses and refills in the ARMv7 perf
backend makes little sense and refers loosely to raw counters that
should be used instead.
This patch removes the comments to avoid any confusion.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Add a NODE level to the generic cache events which is used to measure
local vs remote memory accesses. Like all other cache events, an
ACCESS is HIT+MISS, if there is no way to distinguish between reads
and writes do reads only etc..
The below needs filling out for !x86 (which I filled out with
unsupported events).
I'm fairly sure ARM can leave it like that since it doesn't strike me as
an architecture that even has NUMA support. SH might have something since
it does appear to have some NUMA bits.
Sparc64, PowerPC and MIPS certainly want a good look there since they
clearly are NUMA capable.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: David Miller <davem@davemloft.net>
Cc: Anton Blanchard <anton@samba.org>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1303508226.4865.8.camel@laptop
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The nmi parameter indicated if we could do wakeups from the current
context, if not, we would set some state and self-IPI and let the
resulting interrupt do the wakeup.
For the various event classes:
- hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
the PMI-tail (ARM etc.)
- tracepoint: nmi=0; since tracepoint could be from NMI context.
- software: nmi=[0,1]; some, like the schedule thing cannot
perform wakeups, and hence need 0.
As one can see, there is very little nmi=1 usage, and the down-side of
not using it is that on some platforms some software events can have a
jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).
The up-side however is that we can remove the nmi parameter and save a
bunch of conditionals in fast paths.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If a counter overflows during a perf stat profiling run it may overtake
the last known value of the counter:
0 prev new 0xffffffff
|----------|-------|----------------------|
In this case, the number of events that have occurred is
(0xffffffff - prev) + new. Unfortunately, the event update code will
not realise an overflow has occurred and will instead report the event
delta as (new - prev) which may be considerably smaller than the real
count.
This patch adds an extra argument to armpmu_event_update which indicates
whether or not an overflow has occurred. If an overflow has occurred
then we use the maximum period of the counter to calculate the elapsed
events.
Acked-by: Jamie Iles <jamie@jamieiles.com>
Reported-by: Ashwin Chaugule <ashwinc@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARMv7 dictates that the interrupt-enable and count-enable registers for
each PMU counter are UNKNOWN following core reset.
This patch adds a new (optional) function pointer to struct arm_pmu for
resetting the PMU state during init. The reset function is called on
each CPU via an arch_initcall in the generic ARM perf_event code and
allows the PMU backend to write sane values to any UNKNOWN registers.
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ARMv7 architecture does not guarantee that effects from co-processor
writes are immediately visible to following instructions.
This patch adds two isbs to the ARMv7 perf code:
(1) Immediately after selecting an event register, so that the PMU state
following this instruction is consistent with the new event.
(2) Immediately before writing to the PMCR, so that any previous writes
to the PMU have taken effect before (typically) enabling the
counters.
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
For kernels built with PREEMPT_RT, critical sections protected
by standard spinlocks are preemptible. This is not acceptable
on perf as (a) we may be scheduled onto a different CPU whilst
reading/writing banked PMU registers and (b) the latency when
reading the PMU registers becomes unpredictable.
This patch upgrades the pmu_lock spinlock to a raw_spinlock
instead.
Reported-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Russell reported a number of warnings coming from sparse when
checking the ARM perf_event.c files:
| perf_event.c seems to also have problems too:
|
| CHECK arch/arm/kernel/perf_event.c
| arch/arm/kernel/perf_event.c:37:1: warning: symbol 'pmu_lock' was not declared. Should it be static?
| arch/arm/kernel/perf_event.c:70:1: warning: symbol 'cpu_hw_events' was not declared. Should it be static?
| arch/arm/kernel/perf_event.c:1006:1: warning: symbol 'armv6pmu_enable_event' was not declared. Should it be static?
| arch/arm/kernel/perf_event.c:1113:1: warning: symbol 'armv6pmu_stop' was not declared. Should it be static?
| arch/arm/kernel/perf_event.c:1956:6: warning: symbol 'armv7pmu_enable_event' was not declared. Should it be static?
| arch/arm/kernel/perf_event.c:3072:14: warning: incorrect type in argument 1 (different address spaces)
| arch/arm/kernel/perf_event.c:3072:14: expected void const volatile [noderef] <asn:1>*<noident>
| arch/arm/kernel/perf_event.c:3072:14: got struct frame_tail *tail
| arch/arm/kernel/perf_event.c:3074:49: warning: incorrect type in argument 2 (different address spaces)
| arch/arm/kernel/perf_event.c:3074:49: expected void const [noderef] <asn:1>*from
| arch/arm/kernel/perf_event.c:3074:49: got struct frame_tail *tail
This patch resolves these issues so we can live in silence
again.
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ARM perf_event.c file contains all PMU backends and, as new PMUs
are introduced, will continue to grow.
This patch follows the example of x86 and splits the PMU implementations
into separate files which are then #included back into the main
file. Compile-time guards are added to each PMU file to avoid compiling
in code that is not relevant for the version of the architecture which
we are targetting.
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
